Using photogrammetry to interpret human action on Neolithic monument boulders in Ireland's Cavan Burren

Digital technology has been increasingly employed in the documentation and analysis of archaeology in the last ten years. We utilized user-friendly digital photogrammetry and animation to assist in the analysis of archaeological evidence in Ireland. Our tools were commercially available software, a consumer-grade hand-held or tripod-supported digital camera, and a personal computer. The method was developed for and has been subsequently used by local archaeological surveyors in an extensive documentation of prehistoric settlement features within the Marble Arch Caves Global Geopark in Ireland. The boulder monuments are unusual in that they are made from glacial erratics whose surfaces display traditional North Atlantic rock art and a new sculpting art form. Pieces making up two boulder monuments were digitally manipulated via animation into what is believed to be their original source stone configurations. Their matching surfaces were studied in detail. The process was employed to demonstrate, non-invasively, how the monuments might have resulted from some actions other than weathering. The analysis supports the hypothesis that humans worked the monuments, which, in turn, supports protection of the monuments for further study.